The use of marine vessels to remove debris from the surface or water is well known. However, vessels that serve this function invariably suffer from one or more problems typical with such vessels, including higher maintenance requirements, slow travel speeds, relatively low limits on the amount and type of debris they are capable of collecting in a single outing, instability caused when debris is shifted on board the vessel, an inability to handle long or heavy debris objects, and an inability to accommodate the use of standard debris collection containers such as front loading or roll off containers.
My vessel combines the known elements of a hull having a tapered bow for speed and cost savings, movable port and starboard bow sections to allow for the ingress of debris bearing water, ballast means for raising and lowering the vessel relative to the surrounding water, together with novel gate means and/or a novel debris collecting bucket moving means to produce a fast, efficient, versatile, relatively simple and cost efficient debris collection vessel with a high debris carrying capacity and superior debris handling abilities as compared with anything existing in the prior art.
U.S. Pat. No. 4,921,605 issued May 1, 1990xe2x80x94Chastan-Bagnis et al., describes a debris removal apparatus having, among other elements, a comb and inclined grill combination wherein the comb serves to disengage debris such as algae or seaweed from the grill and to convey the debris over a spill way immediately aft of the grill. This method of collecting and dumping floating debris on board a vessel is, however, inflexible, inefficient and primitive. Such a debris removal system is not capable of effectively and efficiently collecting, handling and dumping large, unwieldy debris items or a large amount of debris.
The xe2x80x9cRover 12xe2x80x9d is a known vessel manufactured by Hewitt (Brockville) Ltd. of Brockville, Ontario, Canada, and is specifically designed for debris collection. The Rover 12 employs a debris removal system having, instead of a comb and grill combination, a debris collection bucket and an independent gate to halt debris. This gate, however, is not well suited to debris collection operations in that it operates independently of the debris collection bucket. During debris collection operation, the gate lifts following the rise of the bucket and lowers once the bucket has returned to the original collection position. As a consequence, a downside of the Rover 12 arrangement is that debris can and often does make its way behind the gate as it is being raised, or becomes lodged below the bucket as it is being lowered. The Rover""s gate design, although previously the best gate and bucket arrangement, is problematic and results in an inefficient debris collection operation with considerable down time for maintenance. A further shortcoming is that when the bucket of the Rover 12 collects debris, it travels vertically and pivots backwards to deposit debris immediately aft of the area in which it is collected. This debris removal system may be capable of collecting somewhat larger debris items than U.S. Pat. No. 4,921,605, but it too is incapable of dumping the collected debris anywhere except in the one area immediately aft of where the debris is collected. This inability to efficiently distribute collected debris on board the vessel seriously limits the amount of debris this vessel can collect in an outing and can adversely affect the vessel""s stability. Moreover, the Rover 12 is also incapable of handling large, unwieldy debris items.
U.S. Pat. No. 5,173,182 issued Dec. 22, 1992xe2x80x94Delbellian, describes a vessel which collects debris from the water surface and dumps it in a debris collection container immediately aft of where the debris is collected. A pair of inboard cranes located on deck near the starboard and port sides of the vessel are used to replace a filled debris collection container with an empty one. This method of distributing collected debris onboard is inefficient and potentially dangerous to crew involved in the container movement process. The shifting of loaded debris collection containers requires considerable time and contributes to vessel instability. Also, the collection method employed by Delbellian is, like the apparatus described in U.S. Pat. No. 4,921,605 and the Rover 12, incapable of handling large, unwieldy debris items.
The present invention is directed towards a marine vessel used for collecting floating debris from surrounding water. The marine vessel includes the well known features of a hull having a tapered bow, port and starboard bow sections moveable laterally between bow open and bow closed positions, an apron located between the bow sections, a debris collection area aft of the apron, a debris dumping area midships and aft of the debris collection area, ballast means for selectively locating the apron between positions above and below the surrounding water, and means for causing the surrounding water to flow over the apron and through the debris collection area when the apron is below the surrounding water.
The marine vessel of my invention includes an open chamber located below and aft the apron and which has defining walls which include water passageways therethrough. It further includes a debris collection bucket having water passageways extending therethrough. The bucket collects debris when it is in a first position where the bucket is located in the open chamber and water containing the debris is made to flow through both the open chamber and the bucket. The vessel incorporates means for moving the bucket between the first position and a second position where the bucket is located at the debris dumping area.
In order to effectively prevent any entry of debris into the collection area when the bucket is removed from the open chamber, the vessel employs gate means on its apron. Advantageously, the gate means cooperates with the bucket and moves between a gate open position when the bucket is located in the open chamber to thereby permit debris to enter into the debris collection area, and a gate closed position to impede entry of debris into the debris collection area. Preferably, the gate means may have water passageways through it to facilitate water flow through the vessel when the gate is in the gate closed position. Since the gate means and the bucket cooperate one with the other so that the position of the gate means is dependent on the bucket, this debris collection system effectively prevents debris becoming lodged on top of the gate or finding its way in behind the gate. This way, a much more efficient debris collection operation is achieved than is possible with the vessels described in U.S. Pat. Nos. 4,921,605 and 5,173,182, and with the Rover 12.
Preferably, means for biasing the gate means in the gate closed position are provided. To this end, one or more extension fingers may be included on the bucket and engagable with a corresponding number of extension finger receiving means included on the gate means. Thus, when the bucket is in the first position, the extension fingers on the bucket maintain the gate means in the gate open position. As a consequence, the bucket remains in contact with the gate such that debris is not able to find its way behind the gate or lodge itself below the bucket.
In accordance with another aspect of my invention, the marine vessel can advantageously include a primary boom which extends centrally and longitudinally of the vessel with one of the boom ends being pivotally connected to the vessel rearward of the debris dumping area, while the other end is pivotally connected to the bucket. This primary boom is telescopically and vertically movable between the debris collection area and the debris dumping area. Further, the bucket is preferably movable from a debris collection position in the debris collection area to a debris dumping position when in the debris dumping area. The primary boom provides the very desirable capability in a debris collection vessel of being able to place collected debris in areas other than the one area directly aft the collection area. Moreover, as the boom moves centrally and longitudinally relative to the vessel, its movement as well as the debris it dumps do not adversely affect the stability of the vessel. In fact, up to a point, the more debris evenly distributed centrally and longitudinally of the vessel, the more stable the vessel may become. Also, the boom is capable of assuming a position whereby its overall height can be minimized to accommodate situations where overhead clearance is an issue.
In accordance with another aspect of my invention, provision can advantageously be made for a secondary boom which is telescopically movable relative to the primary boom and is located at the other end of the primary boom. The secondary boom has grappling means located at its distal end for grappling debris forward of the debris collection area and can be in the form of a pair of pincers pivotally connected to the distal end of the secondary boom. This enables the grasping and handling at and forward of the debris collection area of large, unwieldy items of debris which may be encountered in certain debris collection operations. This permits the vessel to continue debris collection operations notwithstanding encountering large, unwieldy debris items of the sort that would oblige previously existing vessels to halt operations to separately address such debris items.
The pincers, relative to the primary boom, are preferably movable on the secondary boom from a position within the bucket to a position forward of the bucket. When the pincers are not needed they may be stationed in the bucket and positioned so as to interfere as little as possible with the debris collection function of the bucket.